1. Field of the Invention
The present invention relates to a photocathode.
2. Related Background Art
As a conventional photocathode, known is one including a substrate, a photon absorbing layer (light absorbing layer) formed on the substrate, an electron emitting layer formed on the photon absorbing layer, and a mesh-like grid formed on the electron emitting layer, as described in, for example, Patent Document 1 (Japanese Patent Publication No. 2668285). A very small part of the surface of the electron emitting layer is covered with the grid.    Patent Document 1: Japanese Patent Publication No. 2668285